Centrifugal clutch



CENTRIFUGAL. CLUTCH Filed NOV. 27. 1950 2 Sheets-Sheet l Jian. W, 1956 W. H. Krr'ro CENTRIFUGAL CLUTCH 2 Sheets-Sheet 2 Filed NOV. 27, 1950 United States Patent O CENTRIFUGAL CLUTCH William H. Kitto, Evanston, Ill., assignor to G-M Laboratories, Inc., Chicago, Ill., a corporation of Illinois Application November 27, 1950, Serial No. 197,722 17 Claims. (Cl. 192105) This invention relates to a centrifugal clutch of general utility and also to one which has particular utility in an improved floor polishing and scrubbing machine of the type having a motor driven single rotary flat brush.

The principal object of this invention is to provide an improved centrifugal clutch, which accurately operates at a predetermined speed, which provides a resilient drive, which is noiseless in operation, which may be made essentially of stamped metal parts, which may be rapidly and inexpensively manufactured and assembled, which requires no lubrication, which is particularly adaptable for transmitting torque from a motor to a brush in a oor polishing and scrubbing machine, and which also is of general utility.

A floor polishing and scrubbing machine utilizing the novel centrifugal clutch of this invention is fully illustrated and described in a co-pending application Serial No. 197,725 tiled November 27, 1950, by Archie J. McMaster, William H. Kitto, and Kurt Burian, includes a base member which is preferably of an inverted cup shaped configuration. A substantially constant speed single phase induction motor is mounted on the upper side of the base member with the motor shaft extending downwardly through the base member. A phasing reactor is also mounted on the upper side of the base member. A cover is secured to the upper side of the base member and encloses the motor and phasing reactor. The lower end of the motor shaft operates a motor pinion meshing with a cluster gear carried by a bracket secured to the lower side of the base member. The cluster gear also meshes with an output gear carried by a bracket also secured to the lower side of the base member. Mounting means detachably secure a at rotary brush to the output gear to be driven thereby. The novel centrifugal clutch of this invention is located between the motor shaft and the motor pinion. A handle having a bail is pivotally mounted on the side of the frame in transverse alignment with the brush axis for manipulating and controlling the machine.

When the motor is started, it starts under no load and rapidly accelerates to a speed at which the motor torque reaches its maximum value. At this point the centrifugal clutch connects the motor through the gearing to the brush for rotating the same at the desired speed. The

rachine may be readily and easily manipulated and controlled for performing the floor polishing and scrubbing operations. In case the brush should be jammed and fail to rotate on starting or in case the brush shouldgbe stalled during use, the centrifugal clutch will permit the motor to operate at substantial speed thereby avoiding overheating and burning out of the motor under these conditions.

The centrifugal clutch of this invention is carried by the lower end of the motor shaft and includes a drive plate adjustably carried by the motor shaft which in turn carries a plurality of weights urged inwardly by a garter spring. Spring devices between the clutch plate and the weights provide for a resilient drive and eliminate noise.

A clutch cup including a suitable lining is engaged by the weight when the motor speed reaches the desired value and is driven thereby. The clutch cup is journaled for relative rotation on the motor shaft and carries a motor pinion, the motor pinion being coupled to the motor shaft by the centrifugal clutch when the motor is up to speed and .uncoupled therefrom when vthe motor is not up to speed.

Further objects of this invention reside in the details of construction of the centrifugal clutch and in the cooperative relationship between the component parts thereo i Other objects and advantages of this invention will become apparent to those skilled in the art upon reference to the accompanying specification, claims and drawings,

lin which:

Fig. l is an enlarged sectional view through the centrifugal clutch taken along line 1-1 of Fig. 2;

Fig. 2 is a top plan view of the novel centrifugal clutch of this invention;

Fig. 3 is a horizontal sectional view taken through line 3-3 of Fig. l;

Fig. 4 is a sectional view taken along the line 4 4 of Fig. l and showing the clutch disengaged;

Fig. 5 is a view similar to Fig. 4 lbut showing the clutch engaged;

Fig. 6 is an exploded clutch;

Fig. 7 is an exploded -perspective view of the clutch drive plate and weights driven thereby;

Fig. S is an exploded perspective view of the clutch cup assembly;

Fig. 9 is a sectional view taken along the line 9 9 of Fig. 6; and

Fig. l0 is an exploded utilized in the clutch.

Referring now more specifically to the drawings, wherein like parts are designated by the same numerals throughout the various figures', a centrifugal clutch embodying the principles of this invention is shown best in Figs. l and 2. The lower end of a suitable motor shaft 22 carries perspective view of the centrifugal perspective view of the'weight the centrifugal clutch and motor pinion assembly including a clutch drive plate 150, clutch weights 151, a clutch cup 152, and a motor pinion 153. The clutch drive plate is staked at 155 to a hub 156 which in turn is adjustably secured to the motor shaft 22 by means of a set screw 157, the set screw engaging a reduced portion on the motor shaft. Thus, the clutch drive plate 150 is carried and driven by the motor shaft 22. The clutch drive plate includes three fingers 158 for the purpose of driving and guiding the clutch weights. The remaining portions 159 of the drive plate 150 support, guide and separate the main clutch weights 151 and auxiliary clutch weights 166.

There are three main clutch weights 151, each of which is substantially sector-shaped but provided with a clearance radius 161 at the inner end thereof.- Each sector' is provided with a central opening 162 from which is struck downwardly an ear 163. The ear 163 is flared at its end for providing a camming action. Each main weight is also provided at its outer edge with a downwardly extending shoe 164. There are also provided three auxiliary weights 166, each of which is also substantially sectorshaped, having a radius 167 on its inner end, the radius 167 cooperating with the periphery of the hub 156 to limit inward movement of the weights. The auxiliary weight 166 is also provided with a central opening 168 and the connecting web 169 is curved upwardly for the purpose of spacing the outer end of the lower auxiliary weight apart from the outer end of the upper main weight to a distance substantially equal to the thickness of the drive plate 150. This maintains the two weights 151 and 166 in spring, 4 y A V"151 and "1'66 inwardly."andbecauseof thejared ends on therears v$163 "alsoj 'operates-tof maintain the Acurvedv rib -l169 'of'Y theiauxiliary-'weight"166' inengagement with the parallelrelation.v 'Theupper weights 151 are placed on top of" the ^drive-plate 150 vand' the lower lWeights vare placed underneath the drive plate, the openings 162 and 168 of the two weights being in alignment with the fingers 158"ofl thedrive' plate. "U-shaped 'springs""171^ having `slots""1'72` onth'e )ends thereof' are insertedin the jopenings 162 'and y "the ngers"158 of the drive' plate' 150. 'The slots '172 168'ofthe main and auxiliary weights and over receive'the inner endsofthe. main'and auxiliary weights i151 and166 and operate to maintaiirthev inner ends of these weights Vin 'engagement' with'the" drive plate 150. The ears 163 ofthe upper mainweights 151 extend down wardly beyond the ends of theiing'ers 158 and' through "the openings 1'68jinY the lower auxiliary weights. A garte1sp1'ing 173 isfhoked overthese'ears 163. i The" garter therefore, urges the main Iand auxiliary weights yupper main weight 151. Thus, parallel relationshipis maintained: between `the mainv and auxiliary' weightsl and they are both urged inwardly by thejactionof the garter spring.

The outer edges of the ,auxiliary weightst166 engage the inner surfaces of the shoes l164 of the main weights so that both sets of weights are moved inwardly bythe garter springl 173 and therefore operate together. 'The inward movement ,of the weights islir'nited by, the radius 167 of theauxiliaryweights/166 engaging the periphery of the hub 156 of the drive plate. Whenthe weights are so moved inwardlyv the adjacent v"edges '170` of the auxiliary weights are brought .together for the purpose of circumferentially and'radially aligning"the-.auxiliary and main weights. This prevents theweights from becoming cocked and hence causes the'l shoes1'64 to assume a substantially circularv position. In assembling the clutch mechanism the mainweights and'auxiliarywe'ights are brought and held together by thespring clipsr171. The main and `auxiliary weights are""thensandwiched` overthef. drive plate with the springclips engaging thesides! of the fingers 158 of' the "drive, plate. i The adjacent' edges' 170 and the radius 167 "of theauxiliary vweights '166 extend beyond `fthe corresponding .edges andradiusbf the main weightslSl, so that the' main and auxiliary weights may be readily separated" forslippingthempverthe drive vplate in theassem'bly of the 'clutch mechanism. `The spring clips 171'provide a resilient driving connection in 1 the rotationalv direction Abetween thedrive plate 1'50` and -the main and auxiliary weigh'ts`151'and 166.""'These spring clips 171 `also operate ,to preventchat'tering of the weights with'respect to the drive'plate and'thereby eliminate noise.

"""The "clutch cup Ii152'is vprovided with a'iside wall' 175 againstthe inner.' side of whihis 'mounted aclutchlining 1177.' The clutch lining i's'lreld inf'place',it'theclutch v,cup by"`detents l176 fformfed onj'the Vupper'edgevfof' tliejlelutch cup. Since thefriction'betweeni the clutchlining V177 and the'side wall 175 of' the clutchcup is' greaterthanQthe friction of the shoes of the weights, it is not'ne'cessary to permanently securethe'clutchlining to the 'clutch cup. All that is necessary is to maintain theclutch'lining in place and this is accomplished bythe detents 176."`T he center openingof theclutch'cup is provided vwith recesses 179 for receiving lug's' 180 formed onthe upperv end of the motor pinionl 153. Preferably, the-motorfpinion is'made of suitable plastic material such ,asv nylon and the-lugs-180 and recesses 179 form adrive c onnectionbetweenthe nylon motorfpiuion and I,the clutchcup. Y The Iplastic motor -pinion 153- is pressedonto an metallsleeve- 11.82-zwhich is provided at its bottomy with ashoulder '184 toflimitI down- .ward movement; of thefmotor,pinionwith-respect;to the sleeve. The upperfportionof the metal sleeve -182 is `pro- Uvided-with atshoulder-:182'which-receives a collar i181, the collar-operating to;elamp the "clutch cup :152 in drivring engagement:on-themotorrpinion 153. Whentheparts 4are thus assembled,.theguppergend of jthe metal sleeve tion. "Thefrpeenedover portion isground'for-I otherwise formed flat since it servesas an end thrust member between the sleeve 182 and the clutch plate hub 156.

A sintered porous bronze bearing sleeve 186 is interposed between the metal sleeve 182 and the motor shaft 22. The bearing sleeve. has alight interference lit with the motor shaft 22 and has a running lit with the metal sleeve 182. The porous bearing'sleeve 136 isimpregnated with a suitable lubricant for lubricating the running fit and the lubricating action is aidedby-centrifugal force 011 lthe lubricant afforded bythe rotation of the bearing sleeve with themotor shaft.

A thrust bearing for the motorV pinion 153 is provided at the lower end of'the -motor=shaftl22. lt consists of a washer 187 carried by the motor pinion and a second washer 188 carried by the motor shaft. The washer 188 is held in place by a, split washer 189 carried in a suitable groove-on-th'ewlower end"of-the motor shaft.

f -In kassembling-the clutch-mechanism and motor .pinion i'-assembly,='-the motor pinion Y assembly is ybroughtl to its lower-moshpo'sitionwiththe thrust washers `187 and .188

#ini engagement. V Then-therhub 156 of the clutclidrive flplate v150 is secured tothe motor'shaft by the set screw a 157 to provide the proper clearance between the hub 156 1A'and the'fat peened overlportion` 183 of the pinion sleeve 1182.? In this 4way proper end play is provided for'the clutch and motor pinion assembly.

"i When the novel clutchI of vthis invention is used in a machine of the type .described in said co-pending ap- 1= plication Serial No. l97,725,'the centrifugal clutch couples the motor shaf-t to the motor pinion, andfthere is no relative motion therebetween during normal operation. A Relative motion occurs between the motor yshaft'and the motor pinion'only. in star-ting the machine or upon stallingof 1 -the brush while the -motor is'frunning. `Upon starting-the'machinethe'motor starts under'no load and :rapidly-accelerates' to the desired `normal operating speed.

A Wheri'L themotor'speed reaches about 2600 R. P. M. the

fatabou't -3300 R. P.M. If the brush should'stall, the

-motorf-speed-drops to about-2800 R. P.- M. whereupon theclutch-starts to`slip-and the motor-continues to run atV a; speed-ofsomewhat less than -2800 R. l.l M. This j prevents undue "heating" andv burning out of themotor under vthese adverse conditions.

l` Fromthe above'description, it is seen that the present invention-has provided a'novel centrifugal clutch which mayv bejrapidlyandinexpensively manufactured using "essentially sheetrnetal parts. "j In; addition, it is seen that fthev novelfveoustruction and arrangement'of the weight "membersfof^'the`clutch provides improved performance 'and"noiselessoperation and` requires no lubrication.

While for the purposes of illustration one form ofthis invention has beenidisclosed, other forms'thereof may becomeapparent to those skilled in the art upon'reference to *thisv disclosure and, therefore, this invention is ,to` beg-limited only lby the scope` of theappended claims.

I claimas my invention:

. l2 A centrifugal clutchcomprising, a rotatable drive shaft, a drive-'plate secured to the drive shaft for rotation therewith, a'plurality of weights having shoes on Ltheir 'outer edges, .means including spring. means movable: with and radiallyslidably mounting the weights vvkon the drive plateforsubstantiallystraight line radial movement relative to the drive plate to and from extended and retracted positions. and-resiliently vconnecting the weights to;thejdrivel lplatefor resiliently driving f 4the-weights in a rotative direction by the drive plate, additional` spring r means urging the. weights inwardly .funtil overcome,fbygcentrifugal. nforce .whereupon said @weights --slide radially@outwardly;i against t the actionof affamata said last mentioned spring means, and a cup member rotatably mounted on the drive shaft for rotation relative thereto and engaged by the shoes of the weights when the weights slide radially outwardly to be rotated thereby.

2. In a centrifugal clutch having a rotatable sheet material drive plate, a plurality of sheet material weights having shoes on their outer edges, means for radially slidably mounting the weights on the drive plate and for driving the same in a rotative direction by the drive plate spring means urging the weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action of said spring means, the combination comprising a sheet material cup member having an annular side ange, a clutch lining engaging the side flange of the cup member, and detentsI on the edge of the annular side flange for retaining the clutch lining in the cup member.

3. A centrifugal clutch comprising, a rotatable drive shaft, a drive plate having a hub, means for longitudinally adjustably securing the drive plate hub to the drive shaft for rotation therewith, a plurality of weights having shoes on their outer edges, means including generally U- shaped spring means having legs disposed between generally radially extending opposed surfaces on said drive plate and weights for radially slidably mounting the weights on the driveplate and for driving the same in a rotative direction by the drive plate, additional spring means urging the weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action of said last named spring means, a cup member having a hub, and means for rotatably mounting the cup member hub on the drive shaft for engagement of the cup member by the shoes of the weights when the shoes slide radially outwardly for rotating the cup member. l

ci. A centrifugal clutch comprising, a rotatable drive plate having a plurality of radially extending fingers, a plurality of sector shaped weights having shoes on their outer edges and central openings therein overlying the drive plate fingers, said openings being defined by opposed generally radially extending edges, spring means received within the Weight openings and engaging the radial edges of the drive plate fingers and said radially extending edges of the weight openings for radially slidably mounting the weights on the drive plate and resiliently connecting the weights to the drive plate for resiliently driving the weights in a rotative direction, additional spring means urging the weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action of said last mentioned spring means, and a cup member engaged by the shoes of the weights when the weights slide radially outwardly to be rotated thereby.

5. A centrifugal clutch comprising, a rotatable drive plate having a plurality of radially extending ingers, a plurality of main sector shaped Weights on one side of the drive plate having shoes on their outer edges and openings overlying the drive plate iingers, a plurality of auxiliary sector shaped Weights on the other side of the drive plate and having openings overlying the drive plate fingers and having their outer edges engaging the shoes of the main weights, spring means received in the openings of the main and auxiliary weights and engaging the radial edges of the drive plate lingers for radially slidably mounting the main and auxiliary weights on the drive plate and for resiliently connecting the main and auxiliary weights to the drive plate for resiliently driving said weights in a rotative direction, spring means urging the weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action or" said last mentioned spring means, and a cup member engaged by the shoes of the Weights when the weights slide radially outwardly to be rotated thereby.

6. A centrifugal clutch comprising, a rotatable drive plate having a plurality of radially extending fingers, a plurality of main sector shaped weights on one side of the drive plate having shoes on their outer edges and openings overlying the drive plate fingers, a plurality of auxiliary sector shaped weights on the other side of the drive plate and having openings overlying the drive plate fingers and having their outer edges engaging the shoes of the main Weights, spring means received in the openings of the main and auxiliary weights and engaging the radial edges of the drive plate ngers for radially slidably mounting the main and auxiliary weights on the drive plate and for resiliently connecting the main and auxiliary Weights to the drive plate for resiliently driving said weights in a rotative direction, ears on the main weights extending through the openings in the auxiliary weights beyond the ends of the drive plate lingers, a garter spring encompassing the ears for urging the main weights and hence the auxiliary weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action of said garter spring, and a cup member engaged by the shoes of the weights when the weights slide radially outwardly to be rotated thereby.

7. A centrifugal clutch comprising, a rotatable drive plate having a plurality of radially extending fingers, a plurality of main sectors shaped weights on one side of the drive plate having shoes on their outer edges and openings overlying the drive plate ngers, a plurality of auxiliary sector shaped weights on the other side of the drive plate and having openings overlying the drive plate fingers and having their outer edges engaging the shoes of the main weights, spring means received in the openings of the main and auxiliary weights and engaging the radial edges of the drive plate lingers for radially slidably mounting the main and auxiliary weights on the drive plate and for resiliently connecting the main and auxiliary weights to the drive plate for resiliently driving said weights in a rotative direction, spacer means between the main and auxiliary weights beyond the ends of the drive plate lingers, spring means urging the weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action of said last mentioned spring means, and a cup member engaged by the shoes of the weights when the weights slide radially outwardly to be rotated thereby.

8. A centrifugal clutch comprising, a rotatable drive plate having a plurality of radially extending fingers, a plurality of main sector shaped weights on one side of the drive plate having shoes on their outer edges and openings overlying the drive plate fingers, a plurality of auxiliary sector shaped weights on the other side of the drive plate and having openings overlying the drive plate fingers and having their outer edges engaging the shoes of the main weights, spring means received in the openings ofthe main and auxiliary weights and engaging the radial edges of the drive plate fingers for radially slidably mounting the main and auxiliary weights on the drive plate and for resiliently connecting the main and auxiliary weights to the drive plate for resiliently driving said weights in a rotative direction, ears on the main weights extending through the openings in the auxiliary weights beyond the ends of the drive plate iingers, a garter spring encompassing the ears for urging the main weights and hence the auxiliary weights inwardly until overcome by centrifugal force whereupon said weights slide radially outwardly against the action of said garter spring, spacer means between the main and auxiliary weights beyond the ends of the drive plate lingers, and a cup member engaged by the shoes of the weights when the weights slide radially outwardly to be rotated thereby.

9. A centrifugal clutch comprising, a rotatable drive plate having a hub and a plurality of radially extending fingers, a plurality of main sector shaped weights on one side of the drive plate having shoes on their outer edges and openings overlying the drive plate lingers, a plurality s. of .auxiliaryA sector ,shaped weigl1ts;..o1nl the gather.'- side of rthetdrive; plate and. havingopenings overlyingrtheidrive f platefngersnand having their? outer edges; :engaging the rshoes of :the main .weights SpringmeansreCeved; ini the `openings-.ofthe main andauxiliaryweights.l and engaging .Y-

5. the radial edges of'thedrive- .plate ngers1for radially slid- ;a'oly mounting the main ...and auxiliary, lweights f on .the :drive ,plate ;and for resiliently .connecting thefmain and :auxiliary weights to the drive plate for..resilientlydriving said weightsin a rotative .dire,ction,: spring meanszurging` the main weightsand hence the auxiliary weightsvinwardly, the. auxiliaryweights pengaging the drive .plate hub to limitthe inwardmovement of. .the weights, cen trifugal force overcoming ,the-.last mentioned spring means tocause the. weights. to slidelradially.outwardlyzadjaeent the .action ofthe last mentioned=spring means, and acup .member -engaged by the :shoesf of-"the weights ,when the yweights slide radially outwardly:to be rotated thereby.

110.v Aentiifngal. clutch comprising, aV rotatable drive -.,plurality ofmainV sector shaped weights onvoneside of fthe drive plate `having shoes-.ontheinouter edges and openings overlying the drive plate lingers, a'fplurality of auxiliary sector shaped weightson the .otherfside of the ,driveplate andhaving openingsoverlying the drive plate' lingers and. having'. their outer. edges engaging .the shoes V.of the .main weights, spring -means receivedinthe` openings of .the ymain and auxiliaryfweights andrengaging the radialedges of the driveplate iingersforradiallyslidably 1 mountingzthe main and auxiliaryzweightson' the drive plateandfor resilientlyconnecting the main and auxiliary Weights to :thedriveplatefor;resiliently,.driving; said weightsin a rotative direction,I springtmeansurgingfthe lmain weights. and .hence the. auxiliary.; weights. inwardly,

the radial edges of the auxiliary weights extending-beyond' force overcoming .the last mentioned. spring. -means to causethe weightsrtoislidezradially outwardlynagainst the action; of uthe..lastfmentionedspring .meansfnand a .cup member :engaged fby. thershoes of the.- .weightsxwhen the weights 1 slide radially. outwardly Y to be. rotated.- thereby.

1l. A centrifugal clutchncomprising, airotatabledrive plate having ahuband a. plurality ofiradially extending 1. fingers, a plurality ofemain sector shaped weights on one side of the drive plate having shoes on their outer edges Vand openings overlying thedriveplate; fingers, a plurality of auxiliary sectonshapedaweights` ontheothernside of ..the2.drive plate and ,having :1openings-.over1ying the: drive plate-iingers and ,havingptheir .outer.'edges'engagingvthe v shoes ofthe. :mainfweighta spring'y Ineans1'eceived. in-the Aopenings of-` the. main. and lauxiliarytweights :and engaging Hthe radial-edges othedriveplate fingers for radiallyl slidably mounting theumain and .auxiliary...weights fon-.the drive plate;.and forresiliently.connectingzithe main. and auxiliary. weights to. the'..drive;plate. for resiliently. driving said weightsv in airotative. direction, spring meansurging themain weights` and hencerthe eauxiliary .aveights vin- .wardly,I the auxiliary weightsengaging the drive .plate hub to limit the.l rinward; movement of; the.: weights, the .radial -edges ofvtheauxiliarygweights extendingbeyond the radial -1 :edges of 4the' main weights to facilitate.; assemblyf ofzthe weights. on; the. drive .plate and: tov engage each other; for Y radially aligningwthe :.weightsfwhen: they :are retracted inwardly by; the 'lastmentioned...spring. means, centrifugal force. overcoming '.the,` lastf. mentioned4 spring means 1 -to .causerthe weights.` to slide,radiallynoutwardly against'the action of the lastmentioned-.springymeanst and acup .member engaged;-by 1theeshoes.;of; the-Meights when the l 4weights slidearadiallyoutwardly to berotatedfthereby.

12. vA- centrifugalclutch; comprising, airotatableadrive ...-.platenhaving a plurality;of;radially:extending:fingers, a zplurilliy Of.h lmarnsector ishapedtnweightfsi` onsonefside; of

igthegdriveiplatehaving; :shoesion their 1 outer edges..;and 3f-,Openingsoverlyingfgthedriver platengers, a pluralityv of nfauxiliaryfsector;shaped-,weights on the .other sidefof the driyelplate. a nd,.hav,ingr.openings overlyingv the, drive plate .iingersaand having: their ,.o-uter. -edges- A'en gaging the .shoes oithe main weights; spring-means .received in the .openingsaof-.the rrnainiandA anxiliaryzweights and. engaginglthe @radial .edges of the. driveplate ,lingers for radiallyslidably apmountingthenmain.. andauxiliary .weights on.the drive weights to theadrive.- plate;for lresiliently drivingsaid platc-and-for. resiliently'connecting the main and auxiliary r weights. in a rotativefzdirection, ears on the main .weights .extending through: the .openingsin the. auxiliaryweights .beyond the endsnofzthev drive 'plate fingers, a garter spring encompassing. theearsfor maintaining the main and laux- .1=iliary,.=weights 4incontactwithl'the drive'platc andifor urging the main weightsand hence the auxiliary weights inwardlyi.untilovercomeiby centrifugal force whereupon l :saidfweights slide radially outwardly against the action Aof -;plate..l1aving a plurality of radially: extending' ngers, ati,

said-garter. spring-:and a cup member. engaged by the ishoes of the weights whenl the weights slide'radiallyuout- .wardly togbe rotated thereby.

f ,13.--Acentrifugalclutch...comprising, a rotatable drive fiplatefhavingaiplurality ofV radially extending fingers,

.f a pluralityofinain ysector shaped weights on one side ofthe drive.r plate having shoes on theirv outer edges -and .openingsoverlying the drivefplate lingers, a plurality of auxiliary Vsector shaped- Weights on the other side of the =-driveiplateand-having openings overlying the drive plate ingers -and having their outer edges engaging the `shoes of lthe mainweightsyspringmeans received in the openings 'off thel main and auxiliary weights and engaging the lradial edges of the drive -plate fingers for radially slidably Y mountingthe main and auxiliary weights on the drive plate and for resiliently connecting 'the main and auxiliary weights-to the drive-plate for Vresiliently driving said extendingt-hrongh lthe openings in the auxiliary weights weights in a rotative direction, cars on the main weights encompassing the ears for maintaining the main and l Aauxiliary-weights'in contact with the drive plate and for -furgingV the main weights and hence the auxiliary Weights inwardly until overcome -by centrifugal force whereupon said--weights-slide radially outwardly against the action offsaid garter spring, spacer means between the main and-'auxiliary' weights beyond the ends ofl thc drive plate fingers,v andy a cup'member engaged by the shoes of the V'weights when the Weights slide radially outwardly to be rotated thereby.

14. A centrifugalclutch, comprising a rotatable drive yplate, a 'plurality of weights, means generally radially eslidably mounting said weights on one side of said drive plate,.each of said weights having ears extending beyond the opposite side of said drive plate, a garter spring encompassing the ears for urging the weights radially inwardly until overcome by centrifugal force, whereupon the weights slide ,outwardly` against the action of the garter spring, and cam means at the free ends of said 60' ears cooperable with said garter spring for retainingsaid weights on said drive plate.

Vl5. A centrifugal clutch, comprising a rotatable drive plate, a lirst group of Weights radially slidably mounted on-one'side of said drive plate, a second group of weights fw. radially slidably mounted on the opposite side of said drive plate, each of. thel weights in said rst mentioned group l having an ear extending beyond the opposite side of said drive plate and' the-weights of the other' of said groups,

a garter-spring'encompassing said ears for urging said lweightsvinwardly until overcome by centrifugal force,

. whereupon the weights slide outwardly, and cam means at v-thef-freel ends of said ears cooperable with said garter 'sprlngvfor retaining bothvl groups of said Vweights on said -drive plate.

"75.vincludes irneans fonispacing said* othertlgroup of =-weights 16. A centrifugal clutch, as defined in claim 15g-which from said drive plate so as to facilitate relative sliding movement between said drive plate and said other group of weights.

17. A centrifugal clutch, comprising a rotatable drive plate having a plurality of generally radially extending arms, a plurality of weights slidably disposed on said drive plate, each of said weights having an opening overlying one of the arms of said drive plate, an elongated sheet material ilexure spring disposed between a generally radially extending edge of each of said arms and a generally radially extending edge of each of said weights defining the opening therein, whereby to provide a yieldable driving connection between said drive plate and said weights, each of said springs having a slot in one end thereof receiving marginal portions of its associated weight and said drive plate, whereby the springs retain the weights against axial separation from the drive plate.

References lCited in the file of this patent UNITED STATES PATENTS Rushton Feb. 26, Wersall June 4, Leyner Jan. 19, Norris May 7, Raven et al. Apr. 7, Porin Apr. 7, Bruestle Apr. 18,

FOREIGN PATENTS Great Britain I une 28, Switzerland Sept. 1, Germany Mar. 17, France Dec. 5, France Mar. 21, 

